Detector Dogs and Probable Cause

Abstract

In this Article, the Author argues that an alert by a detector dog, standing alone, does not provide enough information to a court to allow it to decide whether the alert established probable cause to search. Given the variability of dogs and handlers, courts need access to the particular dog’s track record in the field to determine the particular dog’s initial rate of accuracy. As the included Bayesian analysis demonstrates, a base rate calculation of some kind is necessary before the determination can be made. The possibility of false positives means that in a given case, an alert by a very accurate dog might not mean that there is even a probability that there is contraband present.